The few dated entries in this notebook cover the period October 1880-January 1881. Most of the book was probably used in 1880. The entries are by Charles Batchelor and Francis Upton. Some of the entries are probably by Francis Jehl and other members of the laboratory staff. Most of the material relates to electric lighting. Included are notes on steam engines, belting, and dynamos; notes and drawings relating to electric power distribution; and notes on lamp experiments. There are also drawings of a telephone switchboard. The book contains 278 numbered pages.

Blank pages: 14-19, 54-93, 106-201, 204-206, 209-258, 263.

Missing page numbers: 21-22, 197-198, 207-208, 241-242, 259-262, 265-268.